Automatic doors are doors that are powered open or powered closed or both. If an automatic door is powered open only, then, it is conventionally spring closed or hydraulically closed. Automatic doors conventionally employ a sensor or switch to activate the door. The sensor detects approaching traffic and may be a motion sensor, infrared sensor, or pressure sensor. The switch is conventionally operated manually and may take the form of a push button, swipe card, or other available switch type access or security system. Alternatively the switch may be activated by pushing or pulling the door, so that once the door detects the movement it completes the open and close cycle. These are also known as power-assisted doors.
Swinging doors are hinged and pivot around an axis in an inward or outward direction or both. Automatic swinging doors are coupled to a source of torque, that is, a door operating apparatus, for providing the force necessary to pivot the door open or closed or both. Most commercially available door operating apparatuses are electromechanical or electrohydraulic and are positioned above the door in an overhead position for ease and economy of installation. Most commercially available door operating apparatuses are spring closed.
It is sometimes desirable to position the door operating apparatus in a sub-floor stratum. The Tormax™ Model TN (Tormax is registered trademark of Landert Motoren AG, Bülach-Zürich, Switzerland) is a floor mounted door operator and is manufactured as an automatic door operator. The Model TN is an underground hydraulic closer with a remotely mounted electric pump system that pushes hydraulic fluid within a floor closer to operate a door. The pump system and electronics are mounted remotely and are not mounted underground. The Model TN is a hydraulic device and is not considered an electromechanical door operating apparatus. Commercially available electromechanical door operating apparatuses designed for use underground or in a sub-floor stratum are unknown.
U.S. Pat. No. 6,176,044 discloses a kit and method for retrofitting electromechanical or equivalent door operating apparatuses. The retrofit kit shown in this patent is employable for converting any door operating apparatus for operating a swinging door from overhead use to underground use. The retrofit kit has had general success in the market place.
SUMMARY OF INVENTION
The invention is directed to an improved retrofit conversion kit for converting a door operating apparatus from overhead use to underground use wherein the improvement includes the addition of a sealing arrangement for protecting the door operating apparatus against moisture and/or dust encroachment within its underground location. The invention is also directed to a method for using this kit. In a preferred embodiment, the door operating apparatus which is to be retrofitted is electromechanical or self-contained electrohydraulic, or is otherwise of a type that is generally intolerant to moisture. Also, in this preferred embodiment, the door operating apparatus is of a type that is designed for operation from a position other than the sub-floor stratum. Typically, the retrofit conversion kit is employed, for converting the door operating apparatus from overhead use to underground use and employs an enclosure to be mounted in the sub-floor stratum beneath the door, wherein all of the door operating apparatus is self-contained.
The problem solved by the invention was not recognized in the prior art. It is disclosed herein that electronic and mechanical components of door operating apparatuses can be negatively affected if they are placed underground or within a floor. There is an enhanced likelihood that moisture or dust or both pan encroach into the mechanical components of the door operating apparatus or the electronic components of the door operating system or both if they are located underground or within a floor. This can cause the components to fail and can create a hazardous situation. Moving parts can corrode and become maintenance issues when not in a sealed environment.
It is further disclosed herein that, the area most susceptible to moisture encroachment is the area where the spindle exits the enclosure to engage the door above. Any seal employed to seal the enclosure with the spindle of the kit described in U.S. Pat. No. 6,176,044 (incorporated herein by reference) must permit rotation of the spindle without compromising the effectiveness of the seal. The seal must also be thin enough to not impact the height requirement of the enclosure within the underground or sub-floor excavation.
A further surprising aspect of the invention was the discovery that the addition of the sealing arrangement enhanced the mechanical performance properties of the device. The addition of the sealing arrangement to the retrofit conversion kit surprisingly provides enhanced lateral support to the spindle when a door coupled thereto experiences major lateral forces.